The Cross Sections of Glaciated Valleys

• Published in: Journal of Glaciology
• Main Author: Lewis, W. V.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1947
• Subjects: Earth-Surface Processes; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s0022143000001222; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000001222

The typical U-shaped cross-section of glaciated valleys is well known but little understood. If a climatic change results in a glacier occupying a deep river valley, and some erosion is assumed to occur wherever the ice makes contact with the bedrock, then a partial change from the “V” to “U” section is to be expected. A more potent agency in such a change is probably the sapping of the valley sides by the alternate freezing and thawing of melt-water flowing down to, and under, the glacier. This has been briefly suggested by de Martonne and worked out somewhat more fully in the case of cirques 1